After not having experienced the problem for a while,
Hotmail is rejecting/putting emails into spam again.Is there a way to prevent this from happening?
Solution : siteground server or my own email adress are on a blacklist.
I have filled out a microsoft form hoping they will respond.
Separate new Gmail adres from siteground employee ended up in spam and firstname.lastname@example.org too. My own Gmail adress was just fine.
Maybe the word siteground in the mail or my site being on a wrong shared hosting could be the problem...outcome is I'll have to wat untill microsoft decides I'm with the good guys.